Apparatus for the countercurrent liquid treatment of yarn



T. L. NASH Oct. 25, 1955 APPARATUS FOR THE COUNTERCURRENT LIQUIDTREATMENT OF YARN Filed Jan. 15, 1952 H ug m m T R N 0 E I r 1% M M .0 AM O H Y \v T B United States Patent Ot'fice 2,721,466 Patented Oct. 25,'1955 APPARATUS FOR THE COUNTERCURRENT LIQUID TREATMENT OF YARN ThomasL. Nash, South Parkershurg, W. Va., assignor to American ViscoseCorporation, Philadelphia, Pa., a corporation of Delaware ApplicationJanuary 15, 1952, Serial No. 266,495

4 Claims. (Cl. 68176) This invention relates to a liquid treatingprocess for continuously moving filamentary material of either naturalor artificial origin. More particularly this invention relates to acontinuous countercurrent liquid treating process wherein thecirculatory effects of the filamentary material in the bath are reducedto a minimum.

Continuous processing of filaments and tows is accomplished by passingthe same successively through various chemical and other liquid treatingbaths. Depending upon the efiectiveness of the bathing process, thefilamentary materials must remain submerged in each of the baths acertain minimum period of time. Attempts to satisfy increased productiondemands at the expense of these minimum bathing time periods have causedimproper processing results. To offset these improper results and yet tosimultaneously speed up production, the so-called countercurrent liquidtreating process has been developed. By this process the flow of theliquid in open liquid treating baths is oppositely directed to themovement of the filament or tow therethrough. In this way the yarn isexposed to a greater quantity of treating liquid in a given period oftime and greater quantities of yarn can be satisfactorily handled.

It has been found, however, that due to the drag effect of the filamentor tow, the bath immediately adjacent thereto circulates in thedirection of the filament or tow movement. By reducing this drag effectit was realized that the yarn could be exposed to still greaterquantities of treating liquid in a given time period and thatfurthermore the greater hydrodynamic forces due to a real andsubstantial countercurrent immediately adjacent the area of filament ortow travel would simultaneously increase the penetration of the surfacefilm of the filaments and thereby speed up the chemical actions whichtake place in the filaments.

It is a principal object of this invention to eliminate thisobjectionable circulatory flow of the bath adjacent the filament or towand to effectuate countercurrent hydrodynamic forces of treating liquidsby providing a series of baffles in the bath through which the filamentand bath are required to move in opposite directions and to therebyfurther increase production by use of existing countercurrent treatingequipment.

Other objects will appear in the course of the following description. Myinvention is illustrated in the accompanying drawing wherein:

Figure 1 is a side elevational view in section of an embodiment of theinvention wherein the yarn passes through a plurality of liquid treatingbaths which are designed in accordance with a first embodiment of thisinvention;

Figure 2 is a plan view of a portion of the embodiment shown in Figure1;

Figure 3 is a section on the line IIIIII of Figure 2;

Figure 4 is an enlarged view of the section on line IV- IV of Figure 3;

Figure 5 is another embodiment showing a modified sectionalconfiguration of a pair of baffles;

Figures 6 through 8 are still further embodiments showing differenttypes of baffles that may be used in practicing this invention.

Referring first to Figure 1 of the drawing, a series of open bathtroughs or vessels 3, 4, and 5 are shown placed end to end. Each ofthese vessels is interconnected between a liquid supply means and aliquid discharge means such that the liquid treating solution passessuccessively from one bath to another. Thus a fresh liquid treatingsolution is supplied to vessel 5 by means of an inlet pipe 6 at one endof the vessel 5 the length of which is longitudinally coincident with apath for transferring a running continuous filamentary materialtherethrough. The treating solution thereupon passes through the vesselfrom left to right in the lengthwise direction of the vessel todischarge pipe 7 at the opposite end of the vessel. Pipe 8 interconnectsdischarge pipe 7 with inlet pipe 9 of bath 4. By a similar arrangement,the liquid treating solution is then passed through bath 4 to adischarge pipe 10 from the left end to the right end of the bath.Likewise, the liquid treating solution passes from left to right throughbath 3 by way of its inlet pipe 11 and its waste discharge pipe 12.Frusto-conical deflector plates 17 surround each of the inlet pipes 6,9, and 11 and reduce turbulence in each of the baths. Thus it is to benoted that the liquid treating solution passes through each of thevessels from left to right without undue turbulence. It is to be notedthat the discharge pipes 7, 10, and 12 extend upwardly through thebottom and terminate sufficiently above the bottom of the trough toassure a minimum liquid level in the bath which is above the lowerextremity, edge, or surface of the downwardly extending bafiles 16 whichwill be more fully described hereinafter.

The hydrodynamic pressure which is employed to circulate the liquidtreating solution between the successive troughs may be developed bymeans of the pumps 13 and 14 shown on the drawing or by any otherconvenient means such as by air jets or steam jets.

Each of the vessels is provided with one or more upwardly extendingbaffies 15 which extend across the full width of the vessel and areaflixed to the bottom thereof. Vertically alined with each of theupwardly extending bafiles is a corresponding number of downwardlyextending baffles 16 which also extend across the full width of thevessel. Downwardly extending baffles 16 are removably mounted in notches40 on the upper surface of the vessel and are retained therein by meansof removable plates 41. This removable feature of the downwardlyextending baflles provides greater ease in lacing the filamentarymaterial between the vertically alined baffles as will be hereinafterdescribed more fully.

While the drawing illustrates this system as embodying three successivebaths, it is to be understood that any greater or lesser number of bathscould be employed within the scope of the invention. Likewise, althoughthe filament or tow is disclosed as being treated with but a singieliquid treating solution, it is to be understood that the filament ortow may be passed in succession through a plurality of different liquidtreating solutions without departing from the spirit of the invention.

As shown in Figures 1 and 2 of the drawing a pair of drums 19 and 20 arejournaled on the upper edge of each of the vessels, one adjacent eachend thereof. As shown in Figures 1 2, 4 and 5, the filamentary materialpasses through a plane that is midway between the opposed edges orsurfaces of the upper and lower baffles as a resultof the positioning ofthe drums 19 and 20 above and in approximately tangential relationshipto such plane. The shaft of drum 19 of each pair extends beyond the edgeof its respective vessel and is driven by means of a mechanicalconnection through gears 33 and 34 and shaft 35 to a rotating source notshown on the 3 drawing. Drums 20 are shown as idler rollers but it is tobe understood that each of the drums 19 and 20 could be driven. Eachpair of drums 19 and 20 are preferably slightly skewed relative to oneanother to cause the filamentary material to helically advancetherealong.

Tracing the manner in which the filamentary material passes from asource such as a sp'inneret and coagulating bath or a wound packagethereof through the liquid treating vessel to a collecting means orsubsequent processing station, the filamentary material 18 passes fromthe source through the squeeze rollers 21 and 22, helically around thedrums and through the bath 3, between bafiles 15 and 16 from right toleft, and between *the squeeze rollers 23 and 24. Likewise, thefilamentary material passes helically around the drums 19 and 20 ofbaths 4 and 5 between associated bafiles 15 and 16 from right to leftbetween respective squeeze rollers and 26, and 27 and 28 and on to thecollecting means or subsequent processing station.

Referring to Figures 2 and 3 of the drawing, it is to be noted that thevertically alined baffles are positioned across the vessels preferablysubstantially perpendicular to the path of filament movement and spacedapart such that a satisfactory amount of bath liquid treating solutionwill flow therethrough. It should be noted that the constrictedrectangular opening 29 between the bafiles provides the only means forthe opposite movement of the filament and the bath solution and that inthis way a truly effective countercurrent spinning process is assured.

It should also be noted that the opposed extremities of each pair ofvertically alined baffles are rounded in cross-section. This feature ofthe present invention prevents undesirable circulatory currents in theflow of the bath solution adjacent the constricted openings between thebaffles.

In Figure 5 of the drawing, a second embodiment of the invention isdisclosed wherein the opposed extremities of the vertically alinedbaffies are rounded in a more gradual manner. The gentle slope of thebaffles in this embodiment permits high liquid flow speeds through thesuccessive baths without increased turbulence therein.

In Figure 6 of the drawing still another embodiment of the invention isdisclosed. In this embodiment of the invention as in the previouslydisclosed embodiment, the contour of the upper surface or edge of theupwardly extending baifie 30 is a straight line. However, the lowersurface or edge of the adjacent downwardly extending baffie includesgrooves 32 through which pass the respective turns of the helices on thefilament advancing drums 19 and 20. This feature of this embodiment ofthe invention increases the flow velocity of the treating liquidadjacent the filamentary material and thereby creates greaterhydrodynamic forces which more effectively penetrate its film surfaces.

Figure 7 and Figure 8 disclose structural modifications of theembodiment of the invention disclosed in Figure 6. In Figure 7 the lowersurface of the downwardly extending baffle includes notches or grooves32'. In Figure 8 both the upper surface of the upwardly extending baffieand the lower surface of the downwardly extending baffle are similarlynotched or grooved as at 32" to accommodate the various helices on thefilament advancing drums.

The apparatus of the above-described invention may be employed byprocessing the filamentary material in various ways such as for washing,desulphurizing, bleaching, sizing, lubricating, and other conditioningprocesses of filamentary materials. Thus the liquid treating solutionswhich are selected to be used in the various baths are dependent uponthe manner in which the yarn is to be ultimately processed. It is to bealso emphasized that the above liquid treating apparatus may be used tocondition or treat any type of yarn, filament, tow, narrow band, ribbon,or other filamentary material of either natural or artificial origin.

While preferred embodiments of the invention have been disclosed, thedisclosure is intended to be illustrative only and it is to beunderstood that changes and variations may be made without departingfrom the spirit and "scope of the invention as defined by the appendedclaims.

I claim:

1. Apparatus for the liquid-treatment of filamentary material comprisinga vessel for containing a liquid and having its length longitudinallycoincident with a path for said material extending through the vessel,means at one end only of the vessel for introducing liquid into it,overflow means at the other end of the vessel for maintaining the liquidtherein at a predetermined level, a fixed baffle intermediate the endsof the vessel extending upwardly from the bottom of the vessel andextending across the entire width of the vessel, a removably mountedbafile extending from a position above the liquid level downwardly to aposition below the liquid level and extending across the entire width ofthe vessel in generally vertical alignment with the first-mentionedbafile and with its lower surface adjacent the upper surface of thefirst-mentioned battle to provide at least one constricted openingbetween the baffles, the aggregate of each such opening providing theentire passageway for flow of the liquid and movement of a filamentarymaterial therebetween, the opposed surfaces of each of the bafileshaving a gradual curvature as viewed from the end of the baffle tominimize turbulence in the liquid, and a pair of rollers one thereofbeing mounted between the baflie and each end of the vessel, the lowerportions of the rollers extending below the predetermined level of theliquid into approximately tangential relationship with a plane midwaybetween the opposed surfaces of the baffies.

2. Apparatus for the liquid-treatment of filamentary material comprisingan open vessel for containing a liquid and having its lengthlongitudinally coincident with a path for said material extendingthrough the vessel, means at one end only of the vessel for introducingliquid into it, overflow means at the other end of the vessel formaintaining the liquid therein at a predetermined level, a fixed baffleintermediate the ends of the vessel extending upwardly from the bottomof the vessel and extending across the entire width of the vessel, aremovably mounted balfie extending from a position above the liquidlevel downwardly to a position below the liquid level and extendingacross the entire width of the vessel in generally vertical alignmentwith the first-mentioned bafile and with its lower surface adjacent theupper surface of the first mentioned bafile to provide at least oneconstricted opening between the bafiies, the aggregate of each suchopening providing the entire passageway for flow of the liquid andmovement of a filamentary material therebetween, the opposed surfaces ofeach of the battles having a gradual curvature as viewed from the end ofthe baffie to minimize turbulence in the liquid, and a pair of rollers,one thereof being mounted between the baffle and each end of the vessel,the lower portions of the rollers extending below the predeterminedlevel of the liquid into approximately tangential relationship with aplane midway between the opposed surfaces of the baffles, and the upperportions of the rollers extending to a level above the upper batlie andthe top of the vessel.

3. Apparatus for the liquid-treatment of filamentary material comprisingan open vessel for containing a liquid and having its lengthlongitudinally coincident with a path for said material extendingthrough the vessel, means at one end only of the vessel for introducingliquid into it, overflow means at the other end of the vessel formaintaining the liquid therein at a predetermined level, a fixed bafileintermediate the ends of the vessel extending upwardly from the bottomof the vessel and extending across the entire width of the vessel, thecontour of the upper edge of the upwardly extending bafile being linearas viewed from the side of the baffle, a removably mounted baffleextending from a position above the liquid level downwardly to aposition below the liquid level and extending across the entire width ofthe vessel in generally vertical alignment with the first-mentionedbaffle, the lower edge of the downwardly extending baflle abutting theupper edge of the upwardly extending bafile, the lower edge of thedownwardly extending bafiie comprising at least one groove whichprovides a constricted opening between the abutting baflies, theaggregate of each such opening providing the entire passageway for flowof the liquid and movement of a filamentary material therebetween, theopposed edges of the bafiles having, at each groove, a gradual curvatureas viewed from the end of the baflies to minimize turbulence in theliquid, and a pair of rollers one thereof being mounted between thebaffle and each end of the vessel, the lower portions of the rollersextending below the predetermined level of the liquid into approximatelytangential relationship with a plane midway between the opposed edges ofthe baffies at each groove.

4. Apparatus for the liquid-treatment of filamentary material comprisingan open vessel for containing a liquid and having its lengthlongitudinally coincident with a path for said material extendingthrough the vessel, means at one end only of the vessel for introducingliquid into it, overflow means at the other end of the vessel formaintaining the liquid therein at a predetermined level in the vessel, afixed baflle intermediate the ends of the vessel extending upwardly fromthe bottom of the vessel and extending across the entire width of thevessel, the upper edge of the upwardly extending baffle including agroove, a removably mounted baffle extending from a position above theliquid level downwardly to a position below the liquid level andextending across the entire width of the vessel in generally verticalalignment with 6 a first-mentioned baflie, the lower edge of thedownwardly extending baffle also including a groove and abutting theupper edge of the upwardly extending bafiie, the grooves in the bafliescommunicating with each other to provide at least one constrictedopening between the abutting baflies, the aggregate of each such openingproviding the entire passageway for flow of the liquid and movement ofthe filamentary material therebetween, the opposed edges of the bafileshaving, at each groove, a gradual curvature as viewed from the end ofthe baffles to minimize turbulence in the liquid, and a pair of rollersone thereof being mounted between the bafiie and each end of the vessel,the lower portions of the rollers extending below the predeterminedlevel of the liquid into approximately tangential relationship", with aplane midway between the opposed edges of the baflles at each groove.

References Cited in the file of this patent UNITED STATES PATENTS1,857,111 Macadam May 31, 1932 1,875,984 Bosshard Sept. 6, 19322,209,950 Nai Aug. 6, 1940 2,308,576 Kornegg Jan. 19, 1943 2,369,809Spangler Feb. 20, 1945 2,441,308 Bond May 11, 1948 2,505,033 Elvin Apr.25, 1950 2,587,619 Hofmann Mar. 4, 1952 FOREIGN PATENTS 463 France Jan.21, 1845

1. APPARATUS FOR THE LIQUID-TREATMENT OF FILAMENTARY MATERIAL COMPRISINGA VESSEL FOR CONTAINING A LIQUID AND HAVING ITS LENGTH LONGITUDINALLYCOINCIDENT WITH A PATH FOR SAID MATERIAL EXTENDING THROUGH THE VESSEL,MEANS AT ONE END ONLY OF THE VESSEL FOR INTRODUCING LIQUID INTO IT,OVERFLOW MEANS AT THE OTHER END OF THE VESSEL FOR MAINTAINING THE LIQUIDTHEREIN AT A PREDETERMINED LEVEL, A FIXED BAFFLE INTERMEDIATE THE ENDSOF THE VESSEL EXTENDING UPWARDLY FROM THE BOTTOM OF THE VESSEL ANDEXTENDING ACROSS THE ENTIRE WIDTH OF THE VESSEL, A REMOVABLY MOUNTEDBAFFLE EXTENDING FROM A POSITION ABOVE THE LIQUID LEVEL DOWNWARDLY TO APOSITION BELOW THE LIQUID LEVEL AND EXTENDING ACROSS THE ENTIRE WIDTH OFTHE VESSEL IN GENERALLY VERTICAL ALIGNMENT WITH THE FIRST-MENTIONEDBAFFLE AND WITH ITS LOWER SURFACE ADJACENT THE UPPER SURFACE OF THE